Experiments are conducted in subjects to describe the extent to which oral ingestion of glycerol, 1 ug/kg body weight, plus 1800 mi of 0.1% NaC1 would result in overhydration. The results are compared to the same water intake without glycerol. Data collected at 40 or 60-min. intervals for 4 h. includes Hct, serum osmolarity, Na, K, C1, P, Ca, BUN, albumin, globulin and glycerol. Studies in progress involve glycerol dosages of 1.5 or 0.5 ug/kg body weight.